Reclosable plastic zipper and bag employing same

ABSTRACT

A reclosable zipper ( 10 ) is provided that includes a female portion ( 12 ) having a first base ( 16 ) that defines a continuous groove ( 22 ), and a male portion ( 14 ) that includes a second base ( 26 ) and a male rib ( 28 ). The male rib extends outwardly from the second base for insertion into the continuous groove and is locked therein when the male and female portions are pressed together. A protective flange ( 32 ) extends outwardly from at least one of the first and second bases proximate the male rib or continuous groove of the reclosable zipper. When the zipper is employed in a packaging bag, such as a plastic bag (44), the protective flange deflects a granular or powdery packaged material away from the male rib and continuous groove, which inhibits clogging of these features and allows the zipper to be closed without interference.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to the packaging art, and more particularly to a reclosable zipper of a type used to close a mouth of a bag.

[0003] 2. Description of the Related Art

[0004] Packaging materials with reclosable plastic zippers that are opened by peeling and resealed by pressing are widely used as packaging bags for granular, powdery and other solid materials mainly due to their light weight and relatively low cost. Although there are a wide variety of reclosable plastic zippers used in packaging materials, most of them are rendered inoperable if the packaged material comes in contact with the zipper as it is inserted into or removed from the bag. Particularly, granular or powdery materials have a tendency to clog the mating portions of the zipper, rendering the zipper inoperable. The limitations specifically minimized and/or eliminated by the present invention include the inoperability of a reclosable zipper due to the insertion or removal of granular and powdery packaged materials from a packaging bag.

SUMMARY OF THE INVENTION

[0005] According to the present invention, a reclosable zipper is provided that includes a female portion having a first base that defines a continuous groove, and a male portion that includes a second base and a male rib. The male rib extends outwardly from the second base for insertion into the continuous groove of the female portion and is locked therein when the male and female portions are pressed together. A protective flange extends outwardly from at least one of the first and second bases proximate the male rib or continuous groove of the reclosable zipper.

[0006] In one embodiment of the present invention, the female portion includes a pair of female hooks that extend outwardly from the first base, wherein the pair of female hooks define the continuous groove. One of the female hooks extends outwardly from the first base a greater distance that the other female hook. The protective flange extends outwardly from the second base proximate the male rib.

[0007] When the zipper is employed in a packaging bag, such as a reclosable plastic bag, the longer female hook and protective flange deflect a granular or powdery packaged material away from the male and female portions, which inhibits clogging of the male and female portions and allows the zipper to be closed without interference.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The features and inventive aspects of the present invention will become more apparent upon reading the following detailed description, claims, and drawings, of which the following is a brief description:

[0009]FIG. 1 is a cross-sectional view of a reclosable zipper according to a preferred embodiment of the present invention.

[0010]FIG. 2 is a cross-sectional view of a reclosable zipper according to another embodiment of the present invention.

[0011]FIG. 3 is a cross-sectional view of a reclosable zipper according to another embodiment of the present invention.

[0012]FIG. 4 is a cross-sectional view of a reclosable zipper according to another embodiment of the present invention.

[0013]FIG. 5 is a cross-sectional view of the reclosable zipper of FIG. 1, showing the male and female portions of the zipper molded into the side walls of a packaging bag.

[0014]FIG. 6 is a cross-sectional view of a packaging bag employing the reclosable zipper of FIG. 1, showing insertion of a packaged material into the bag.

[0015]FIG. 7 is a cross-sectional view of the packaging bag of FIG. 6, showing removal of the packaged material from the bag.

[0016]FIG. 8 is a cross-sectional view of a packaging bag employing the reclosable zipper of FIG. 3, showing insertion of a packaged material into the bag.

[0017]FIG. 9 is a cross-sectional view of the packaging bag of FIG. 8, showing removal of the packaged material from the bag.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Referring now to the drawings, preferred embodiments of the present invention are shown in detail. Referring to FIG. 1, there is shown a reclosable zipper 10 that includes a female portion 12 and a male portion 14. Zipper 10 is preferably manufactured of a lightweight, flexible plastic, such as polyethylene and the like, by extrusion, molding or other known processes for forming plastic and other polymeric materials.

[0019] Female portion 12 is defined by a first base 16 having a pair of female hooks 18, 20 that extend outwardly therefrom. Female hooks 18, 20 cooperatively define an elongated channel or groove 22. Each of female hooks 18, 20 is provided with a catch 24 that extends inwardly toward groove 22. As shown in FIG. 1, and for reasons that will be described in detail below, one of female hooks 18 extends outwardly from first base 16 a greater distance than the other female hook 20.

[0020] Male portion 14 is defined by a second base 26 having a male rib 28 that extends outwardly therefrom. Male rib 28 is provided with a head portion 30 that cooperatively engages catches 24 on female hooks 18, 20 to retain male rib 28 in groove 22 once it is inserted therein. Because male rib 28 must be pressed into groove 22, it is preferred, but not required, that male rib 28 be more rigid than female hooks 18, 20. Similarly, for the same reasons, it is also preferred, but not required, that female hooks 18, 20 be more elastic than male rib 28 to allow them to flex and accommodate insertion of male rib 28 therebetween. However, it will be appreciated that a single material may be employed to manufacture zipper 10, the properties of this material exhibiting a balance between the rigidity preferred for male rib 28 and the elasticity preferred for female hooks 18, 20.

[0021] For convenience of description, reclosable zipper 10 is described as having a male rib 28 and a female groove 22, wherein a head portion 30 of the male rib 28 is received by the female hooks 18, 20 of the cooperating female groove 22, but it will be understood and appreciated by those of skill in the art that certain principles of the invention may apply to other modified forms of the zipper closure. Similarly, it will be appreciated that the claims are not limited to the specific form of the rib and groove illustrated in the drawings and described herein.

[0022] As illustrated in the embodiment of FIG. 1, male portion 14 is also provided with a protective flange 32 that extends outwardly from second base 26. Protective flange 32 is provided proximate male rib 28, but not too close as to inhibit insertion of male rib 28 into groove 22. Protective flange 32 extends from second base 26 at least the same distance male rib 28 extends from second base 26 and preferably slightly farther, for reasons that will be detailed below. Protective flange 32 may be disposed substantially perpendicular to second base 26, as shown in FIG. 1, or at least a portion if not all of protective flange 32 may be disposed at some angle relative to second base 26.

[0023] A support flange 34 also extends from second base 26 to support the portion of first base 16 proximate female hooks 18, 20. Support flange 34 cooperates with protective flange 32 to support male rib 28 in groove 22, and functionally inhibits unintentional separation of male and female portions 12, 14.

[0024]FIG. 2 illustrates another embodiment of the present invention. In this embodiment, a zipper 10′ is provided that includes a female portion 12′ having a first base 16′ and a male portion 14′ having a second base 26′. Unlike zipper 10 described above, both first and second bases 16′, 26′ include a protective flange 32A and 32B, respectively. Also, unlike the female portion 12 of zipper 10 described above, female portion 12′ of zipper 10′ may include female hooks 18′, 20′ that are substantially the same length.

[0025]FIG. 3 illustrates another embodiment of the present invention. In this embodiment, a zipper 10″ is provided that includes a female portion 12″ having a first base 16″ and a male portion 14″ having a second base 26″. Unlike zippers 10, 10′ described above, second base 26″ includes a pair of protective flanges 32C, 32D, which are positioned on either side of male rib 28″. Additionally, first base 16″ includes a protective flange 32E that is longer than protective flange 32D. Alternatively, as shown in FIG. 4, protective flange 32E may be shorter than protective flange 32D.

[0026] Referring to FIG. 5, first and second bases 16, 26 are each formed with a pair of elongated flanges 37 and 39 that extend away from first and second bases 16, 26. Flanges 37, 39 provide additional surface area to secure zipper 10 to a packaging bag. Flanges 37, 39 of zipper 10 may be secured to the packaging bag by heat welding, ultrasonic welding or other known process for securing one polymeric material to another. Although not illustrated, it will be appreciated that any of the embodiments shown in FIGS. 2-4 may also be integrally formed with flanges 37, 39 in a similar manner.

[0027]FIGS. 6 and 7 illustrate a flexible bag 44 of lightweight plastic, such as polyethylene or like polymer, having a reclosable zipper 10 according to the principles of the present invention. The plastic used as the material for zipper 10 may be the same type or a different type of plastic used for the main body of the bag as long as it exhibits the material properties need for zipper 10 to function. Preferably, to the portion of the zipper which should exhibit high rigidity is employed a plastic having a high rigidity, while to the portion thereof which should exhibit elasticity is employed a plastic exhibiting the required elastic properties. However, it will be appreciated that a single material may be employed to manufacture bag 44, the properties of this material exhibiting a balance between the properties preferred for the respective portions of the zipper.

[0028] Bag 44 includes a pair of opposing side walls 40, 42 that define an openable mouth 46. Mouth 46 includes the elongate reclosable zipper 10 extending across the inside thereof. Female portion 12 and male portion 14 of zipper 10 are shown in FIGS. 6 and 7 as being non-interlocked.

[0029] In FIGS. 6 and 7, the longer female hook 18 and protective flange 32 are positioned inwardly of groove 22 and male rib 28, respectively, toward the inside of bag 44. To fill bag 44 with a packaged material 48, as shown in FIG. 6, an end 50 of a fill tube 52 is inserted into bag 44 past protective flange 32 and the longer female hook 18. Thus, as bag 44 is filled, none of the packaged material 48 comes into contact with male rib 28 and female groove 22 of zipper 10, allowing zipper 10 to be closed without interference.

[0030] When bag 44 is emptied, as shown in FIG. 7, protective flange 32 and the longer female hook 18 deflect the packaged material 48 away from the male and female portions of zipper 10. Specifically, because protective flange 32 is longer than male rib 28, the packaged material 48 is completely deflected away from male rib 28. Similarly, because female hook 18 is longer than female hook 20, the packaged material 38 is completely deflected away from groove 22. Thus, as bag 44 is emptied, none of the packaged material 48 becomes attached to or clogs male rib 28 or female groove 22, allowing zipper 10 to be re-closed without interference.

[0031] Alternatively, although not illustrated, each portion of zipper 10 may be inverted such that protective flange 32 and the longer female hook 18 face the opening or mouth 46 or outside of bag 44. This configuration would be useful where the bag is emptied using a suction tube that is inserted past male rib 28 and female groove 22, and is filled in a manner that would normally allow the packaged material to contact male rib 28 and female groove 22, but for the protective flange 32 and the longer female hook 18 deflecting the packaged material away from these features.

[0032] The embodiments illustrated in FIGS. 2 and 3 are also employable in bag 44 and function in manner similar to the embodiment shown in FIGS. 1, 6 and 7 to deflect a packaged material away from male rib 28 and female groove 22. For example, FIGS. 8 and 9 illustrate a bag 44″ employing the zipper 10″ shown in FIG. 3. Unlike the embodiment shown in FIGS. 1, 6 and 7, no fill tube 52 is required to insert the packaged material 48″ into bag 44″. Instead, as shown in FIG. 8, protective flanges 32D and 32E deflect the packaged material 48″ away from male rib 28″ and female groove 22″. Thus, as bag 44″ is filled, none of the packaged material 48″ comes into contact with male rib 28″ or female groove 22″, allowing zipper 10″ to be closed without interference.

[0033] When bag 44″ is emptied, as shown in FIG. 9, protective flange 32C and the longer female hook 18″ deflect the packaged material 48″ away from male rib 28″ and female groove 22″. Thus, as bag is emptied, none of the packaged material 48″ becomes attached to or clogs male rib 28″ or female groove 22″, allowing zipper 10″ to be re-closed without interference.

[0034] Although certain preferred embodiments of the present invention have been described, the invention is not limited to the illustrations described and shown herein, which are deemed to be merely illustrative of the best modes of carrying out the invention. A person of ordinary skill in the art will realize that certain modifications and variations will come within the teachings of this invention and that such variations and modifications are within its spirit and the scope as defined by the claims. 

What is claimed is:
 1. A reclosable zipper (10) comprising: a female portion (12) having a first base (16) that defines a continuous groove (22); a male portion (14) that includes a second base (26) and a male rib (28) extending outwardly from the second base (26) for insertion into the continuous groove (22) and being locked therein when the male and female portions are pressed together; and a protective flange (32) that extends outwardly from at least one of the first and second bases proximate the male rib or the continuous groove of the reclosable zipper.
 2. The reclosable zipper of claim 1, wherein the protective flange extends outwardly from the second base proximate the male rib.
 3. The reclosable zipper of claim 2, wherein the protective flange extends outwardly from the second base a greater distance than the male rib.
 4. The reclosable zipper of claim 1, wherein each of the first and second bases includes a protective flange (32A, 32B), the protective flanges extending outwardly from each of the first and second bases proximate the continuous groove and the male rib, respectively.
 5. The reclosable zipper of claim 1, wherein the second base includes a pair of protective flanges (32C, 32D), the protective flanges extending outwardly from the second base on either side of the male rib.
 6. The reclosable zipper of claim 1, wherein the female portion includes a pair of female hooks (18, 20) that define the continuous groove.
 7. The reclosable zipper of claim 6, wherein one of the female hooks (18) extends outwardly from the first base a greater distance that the other female hook (20).
 8. The reclosable zipper of claim 6, wherein the male rib includes a head portion (30) that is engaged by the female hooks when the male rib is inserted into the continuous groove.
 9. The reclosable zipper of claim 1 further including a support flange (34) that extends outwardly from the second base.
 10. A reclosable zipper (10) comprising: a female portion (12) that includes a pair of female hooks (18, 20) that extend outwardly from a first base (16), the pair of female hooks defining a continuous groove (22), wherein one of the female hooks (18) extends outwardly from the first base a greater distance that the other female hook (20); and a male portion (14) that includes a second base (26) and a male rib (28) that extends outwardly from the second base for insertion into the continuous groove and being locked therein when the male and female portions are pressed together; and a protective flange (32) that extends outwardly from the second base proximate the male rib.
 11. A reclosable packaging bag (44) comprising: a pair of opposing sides (40, 42) that define an openable mouth (46) that includes an elongate reclosable zipper (10) extending across the inside of the mouth; and wherein the reclosable zipper (10) includes a female portion (12) having a first base (16) that defines a continuous groove (22), a male portion (14) that includes a second base (26) and a male rib (28) extending outwardly from the second base for insertion into the continuous groove and being locked therein when the male rib and the continuous groove are pressed together, and a protective flange (32) that extends outwardly from at least one of the first and second bases proximate the male or female portion of the reclosable zipper.
 12. The reclosable packaging bag of claim 11, wherein the protective flange extends outwardly from the second base proximate the male rib.
 13. The reclosable packaging bag of claim 12, wherein the protective flange extends outwardly from the second base a greater distance than the male rib.
 14. The reclosable packaging bag of claim 11, wherein each of the first and second bases includes a protective flange (32A, 32B), the protective flanges extending outwardly from each of the first and second bases proximate the continuous groove and the male rib, respectively.
 15. The reclosable packaging bag of claim 11, wherein the second base includes a pair of protective flanges (32C, 32D), the protective flanges extending outwardly from the second base on either side of the male rib.
 16. The reclosable packaging bag of claim 11, wherein the female portion includes a pair of female hooks (18, 20) that define the continuous groove.
 17. The reclosable packaging bag of claim 16, wherein one of the female hooks (18) extends outwardly from the first base a greater distance that the other female hook (20).
 18. The reclosable packaging bag of claim 16, wherein the male rib includes a head portion (30) that is engaged by the female hooks when the male rib is inserted into the continuous groove.
 19. The reclosable packaging bag of claim 11 further including a support flange (34) that extends outwardly from the second base. 